/***********************************************************************
 * BinTrotter : BitTorrent library/client for the Android operating system.
 *  
 * Copyright (C) 2009, Christopher David Stones (chris.stones@gmail.com)
 * 
 * This program is free software; you can redistribute it and/or modify
 * it under the terms of the GNU General Public License as published by
 * the Free Software Foundation; either version 3 of the License, or
 * (at your option) any later version.
 * 
 * This program is distributed in the hope that it will be useful,
 * but WITHOUT ANY WARRANTY; without even the implied warranty of
 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
 * GNU General Public License for more details.
 * 
 * You should have received a copy of the GNU General Public License
 * along with this program. If not, see <http://www.gnu.org/licenses/>.
 ***********************************************************************/

package org.bintrotter.apeer.sendstates;

import java.io.IOException;
import java.nio.ByteBuffer;
import java.nio.channels.SocketChannel;

import org.bintrotter.apeer.Peer;

public class Bitfield implements SendState {

	private Peer 			m_peer;
	private SocketChannel 	sc;
	private ByteBuffer		bb_payload;
	private ByteBuffer		bb_header;
	
	public Bitfield(Peer peer) {
		
		m_peer = peer;
		sc = null;
		bb_payload = bb_header = null;
	}
	
	@Override
	public void reset() {
	
		byte[] bf = m_peer.outBitField();
		
		if(bf!= null) {
		
			bb_payload = ByteBuffer.wrap(bf);
			
			bb_header = ByteBuffer.allocate(5);
			bb_header.putInt(1 + bf.length).put((byte)5).rewind();
			
			sc = m_peer.channel();
		}
	}

	@Override
	public States update() {

		
		if(bb_header == null)
			return States.IDLE;
		
		try {
			
			if(bb_header.hasRemaining())
				sc.write(bb_header);
			
			if(bb_header.hasRemaining()==false)
				sc.write(bb_payload);
			
			if(bb_payload.hasRemaining() == false) {
			
				bb_payload = bb_header = null;
				sc = null;
				
				return States.IDLE;
			}
			
		} catch(IOException ioe) {	
			
			bb_payload = bb_header = null;
			return States.SHUTDOWN;
		}
		
		return States.BITFIELD;
	}
}

